Mark 1:25

Verse 25. And Jesus rebuked him. Chode him, or commanded him, with a threatening, to be still. This was not the man that he rebuked, but the spirit, for he instantly commanded the same being to come out of the man. In all this Jesus did not once address the man. His conversation was with evil spirit; proving conclusively that it was not a mere disease, or derangement---for how could the Son of God hold converse with disease, or delirium?--but that he conversed with a being, who also conversed, reasoned, cavilled, felt, resisted, and knew him. There are, therefore, evil spirits; and those spirits have taken possession of men.

Hold thy peace. Greek, Be muzzled. Restrain thyself. Cease from complaints, and come out of the man. This was a very signal proof of the power of Jesus, to be able by a word to silence an evil angel, and, against his will, to compel him to leave a man whom he delighted to torment.

Mark 1:34

Verse 34. And suffered not the devils to speak, because they knew him. They knew that he was the Messiah. If they had spoken, they would have made that known to the people. Jesus was not desirous, at that time, that that should be publicly known, or his name be blazoned abroad. The time had not come when he wished it to be promulgated, and he therefore imposed silence on the evil Spirits.

(1) "because they knew him" or, "to say that they knew him"
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